[160m] N2XE Beacon On Now! 3545.5 KHz, 12mW

[Ford Peterson]

It seems to me that this is somewhat of a bogus experiment.  I just did a quick test with Pat-W0OPW, 10 miles away.  An HP 606 into a HP-8555/HP8552 spectrum analyzer.  I was using a 80M vertical and he was using an 80M dipole of sorts.  -20dBm was clearly audible but severely noise limited on his end.  I had to listen over the phone as Pat is nearly deaf.

10 miles with -20dBm is 1,000,000 miles / watt.  Cross polarized ground wave.  I'm tempted to listen between two antennas on my own property!

If I could find another station in the right proximity, with a decent antenna and an op with ears, I'm certain 2,000,000 miles is a simple chip shot.

According to my calculations, 3.56MHz has a path loss as follows (no skip)

-45    1 mile
......
-65  11 miles
-70  20 miles
-75  35 miles
-80  63 miles
-85  112 miles
-90  198 miles

Now, cross polarized ground wave is what?  Maybe another -25 dB?  (-20 + -65 + -25 = -110dBm)  This is about as good as it gets with normal back ground noise.  Throw sky wave propagation into the mix and you have another attenuation of -15dB/skip.  

My conclusion?  The best miles/watt will occur with a very close antenna.  Like < 1 mile away.  Then stuff lots of attenuation into the mix and you will have your 2,000,000 miles / watt.  A quick test between the beverage and the transmit antenna is that I can easily copy a -60dBm signal.  They are 200 ft apart.  Thats 37,878,788 miles/watt...

What does it all mean?

Ford-N0FP
ford at cmgate.com